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Abstract Part I: The susceptibility of certain varieties of wheat to infestation with the Khabra beetle, Trogodrma granariun as well as the biological aspects of the insect when bred on the tested varieties. All trials were carried out 35 oc and 65±5 R.H. The varieties of wheat grains tested were: Gamiza 7, Giza 168, Sakha 93, Sohag 3, Seds 12 and Benswaif 4 The main results obtained are as follows: 1-Susceptibility studies: The most preferred varieties for T.granarium were Benswaif 4 wheat and the least susceptible were Giza 168 wheat. 1-1-Degree of infestation with Trogoderma granarium (adult) between the different varieties: The highest and lowest grain damage were sustained by the varieties Beni-swaif 4 and Giza 168 which was 87.66% and 47.54% resp. In non-choice test, meanwhile it was 79.74% and 44.555% in free-choice test.1-2-:Determination of weight loss of wheat grains varieties infested with Trogoderma granarium (choice& non choice): Wheat varieties differed significantly in percentage weight loss. Beni-swaif 4 variety had the highest weight loss(19.8% and 25%) in free choice and non choice tests respectavily.while ,the lowest weight loss Giza 168 (10.2%) and Sed 12 (5.3%) varieties at two previous tests. 1-2-1- weight loss of wheat grains varities infested with Trogoderma granarium(3rd instar) The highest perecentage grains weight loss was recorded for Beni-swaif 4 variety (21%) followed by Sohag 3 (15.7%) while, Giza 168 and Seds 12 varieties were recorded the minimum of weight loss percentage (5.0 and 5.3 % resp.). 1-3-Oviposition preference of Trogoderma granarium between the different varieties(Mean number of egg): It is apparrent that there were differences among the varieties for oviposition preference on beni- swaif 4 and Gamiza 7 which received the highest number of eggs. The mean number of eggs laid on Beni- swaif 4 variety was 116 and 132 eggs in non and free choice method respectively .Meanwhile, In case of (Giza 168) there the least acceptable food for eggs laying ,since the meannumber of eggs laid were 80.0 and 48.75 eggs at non and free choice respectively . 1-4-Role of wheat varieties on mean number of hatchability : Egg hatchability (%) ranged between 97.42 on Beniswaif 4 and 81.9 on giza 168 in non-choice test meanwhile, it was 95.63 and 88.53 in the two previous varieties in freechoice test resp. Results of free-choice and non-choice tests pointed to that, Beni-swaif 4 was more preferable to Trogoderma granarium while Giza 168 was least preferred to insect. 1-5-_The whole developmental period of Trogoderma granarium on different varities In non-choice method, data revealed on that ( beniswaif 4) and ( Gamiza7), since the mean developmental period was 64.6 and 64.2 days respectively , while the shortest ( 58.0) was recorded on (Giza 168). In free-choice method, It is clear that there is a great variation among the cultivars for MDP .The shortest duration recorded was 52.6 days on (beni swaif 4) ,while the longest period 63.0 days in (Giza 168) . 1.6. Mean number of progeny: Beni-Swaif 4 and Gamiza7 were the most susceptible wheat varieties. These varieties were general more preferred to progeny of insect to in free choice method, meanwhile, Bani-Swaif 4 and Sohag 3 gave the mostpreferred to progeny of insect in non-choice test. While (Giza 168) and (Sakha 93) were the least in this respect. 1-7- Dobie index (D .I) of tested wheat varities after infestation by Trogoderma granarium Beni-swaif 4 variety was the most susceptible variety, since its DI recorded (3.3% and 3.7%) in non-choice and freechoice tests. The remaining varieties were least susceptible,since, the recorded DI vaules 2.6% and 3.0% for Giza 168 and Sohag 3 varieties in non-choice and free-choice tests resp. 1-8- Detremination of chemical characters of tolerant and susceptible varieties Chemical components of grain varieties indicated that feeding activity of Trogoderma granarium larvae on Beni-swaif4 variety results in significant increase in lipids and crude fiber. Results marked also that the highly susceptible of (Beni-swaif 4) variety resulted in significant decreases in total carbohydrates and proteins. Meanwhile, the results proved that (Giza 168) variety gave an increase in total carbohydrates and protein, also, decreases in lipids and crude fibre in previous resistant variety. Part II: The current study aimed to evaluate the insecticidal activity of some natural materials for the control of the Trogoderma granarium (adult and larvae) infestation on wheat grains. The materials used in this study are Emamactin benzoate, silica gel, Moringa oil and jojoba oil .Emamactin benzoate is higher toxic to T.granarium therefore selected for further studies i.e. 1- The persistence of their insecticidal efficiency. 2- Effect on reproductive potential number of deposited eggs and number of emerged adults. 3- Effect on some content of main metabolites and the activity of some enzymes. 4- Effect on water absorption and germination of treated wheat grains. The following is a brief summary on the obtained results findings and observation: 1-Insecticidal efficiency of treated matarials on T.granarium adults and larvae:- The obtained data indicate that the adults and larvae mortality increased with increasing concentrations of Emammctin benzoate,silica gel,Moringa oil and Jojoba oil and with increasing exposure time, i.e. a potential linear relationship between the concentrations and percentages mortality exists. The toxicity values of the tested matarials were arranged according to LC50 values in the following order: Moringa oil< Jojoba oil < Silica gel < Emamactin benzoate.2-Residual activity of the tested treatments on Trogoderma granarium adults and larvae after different storage periods:- -The tested compounds Persistence activity gradually decreased with extension of storage period .25 weeks for emamactin benzoate in adult stage and 17 weeks for larvae, 29 weeks for silica gel in adult stage and 24 weeks for larvae, 31 weeks for jojoba oil in adult and 24 weeks for larvae and 27 weeks for moringa oil in adult but in larvae 18 weeks. 3-The effect of four tested materials on reproductive Potential of Trogoderma granarium adults:- - Effect of four tested materials prevented the number of egg laid by T.granarium except in silica gel which recorded a few number of egg laying at LC50 &LC95 values (60,16) eggs. All treatments that cause the non-egg laying, have not shown any adults ie.100%, silica gel showed a reduction in adult emergency. 4-Biochemical studies:- Results were carried out after treatment of the pest with LC50 values of the four tested materials. 1- The four tested materials, caused significant decrease in the total proteins contents of Tgranarium adults and larvae, compared with control. 2- Emamactin benzoate insecticide caused decrease in the activity of trehalase,invertase and amylase enzymes in adults of T.granarium. but,in larvae emamactin benzoate, caused increase in the activity of amylase and a decrease the activity of trehalase,invertase. Silica gel caused increase in the activity of trehalase enzyme and a decrease in the activity of invertase and amylase enzymes in adult. While in larvae caused increase in the activity of invertase enzyme and a decrease in the activity of trehalase and amylase enzymes. Jojoba oil caused increase in the activity of trehalase,invertase and amylase enzymes in adults of T.granarium. but,in larvae caused decrease in the activity of trehalase enzyme and caused increase in the activity of invertase and amylase enzymes. Moringa oil caused decrease in the activity of trehalase,invertase and amylase enzymes in adults of T.granarium. but,in larvae caused decrease in the activity of invertase enzyme and caused increase in the activity of trehalase and amylase enzymes compared to control. 3-Emamactin benzoate caused decrease the activity acid phosphatase enzyme and the alkaline phosphatase enzyme in the body of the tested insect adult and larvae .Silica gel benzoate caused decrease the activity acid phosphatase enzyme and increase the activity the alkaline phosphatase enzyme in adult but, in larvae caused increase the activity acid phosphatase enzyme and decrease the activity the alkaline phosphatase enzyme . Jojoba oil caused increase the activity acid phosphatase enzyme and the alkaline phosphatase enzyme in the body of the tested insect adult while, in larvae caused decrease the activity acid phosphatase enzyme and the alkaline phosphatase enzyme. Moringa oil caused decreases the activity acid phosphatase enzyme and the alkaline phosphatase enzyme in the body of the tested insect adult and larvae compared to control.4-Effect of four tested materials on seeds viability:- Three of treatments (emamactin benzoate, moringa oil and jojoba oil) in this investigation affect the germination and water absorption of the wheat seeds at initial treatment and also after storage period, but silica gel did not affect the germination and water absorption of the wheat seeds at initial treatment and also after storage period. |